Gas Chromatography Determining BTEX in Water

随着国民经济的快速发展,工业产业得到了较大程度的发展,在创造经济效益的同时也带来了环境危害.其中,苯系物是水资源中最重要的污染物之一.文章就气相色谱法对饮用水中苯系物测定进行了分析.     

Genome-wide association study of flowering time and grain yield traits in a worldwide collection of rice germplasm

A high-density haplotype map recently enabled a genome-wide association study (GWAS) in a population of indica subspecies of Chinese rice landraces. Here we extend this methodology to a larger and more diverse sample of 950 worldwide rice varieties, including the Oryza sativa indica and Oryza sativa japonica subspecies, to perform an additional GWAS. We identified a total of 32 new loci associated with flowering time and with ten grain-related traits, indicating that the larger sample increased the power to detect trait-associated variants using GWAS. To characterize various alleles and complex genetic variation, we developed an analytical framework for haplotype-based de novo assembly of the low-coverage sequencing data in rice. We identified candidate genes for 18 associated loci through detailed annotation. This study shows that the integrated approach of sequence-based GWAS and functional genome annotation has the potential to match complex traits to their causal polymorphisms in rice.     

重申柏拉图——正义之城的美学问题

关于柏拉图美学已属老生常谈,但旧学可以新说.事实上,以"放逐诗人"闻名于世的这位哲人最初的人生志愿,是成为一位荷马那样的诗人.意识到这一点有助于我们重新认识柏拉图美学的价值所在.在某种意义上,他的政治哲学转型意味着一种以"正义论"为核心的伦理美学的奠基.所谓"正义之城的美学问题",也就是作为"美本身"的"终极善"的逻辑确定性何以认定的困惑.围绕这个问题展开的相关讨论,对于当下普遍缺乏真正的"问题意识"的中国式美学研究,无疑具有重要的启发意义.     

钢架构拆除技术方案探讨

通过对长岭220 kV变电站的母线改造安装工程的调研,同时通过对AIS与GIS变电站所用设备的分析对比,阐述了改建工程中旧架构与设备拆除的重点和难点。     

Distributed Dynamic Navigation for Sensor Networks

Navigation with sensor networks has shown many advantages and great potential in many scenarios.Previous works have mainly focused on selecting the shortest path to navigate an internal user out of an emergency field.However,they did not consider variations of the dangerous areas which usually occur in practical applications.This paper presents an efficient dynamic routing algorithm to successfully guide users to the destination exit.The navigation goal is looking for a safe and short path to enable the user to escape from a dangerous area as fast as possible.Without knowing the locations of the nodes,the user is guided by a sequence of sensor nodes to pass through the dangerous areas.The algorithm ensures the navigation path security by predicting the dynamic changes affecting the navigation path.The performance of this approach is evaluated using extensive simulations to validate its effectiveness.Simulations show that the approach is scalable and performs well in various settings.     

抗粘、耐酸汽车钢化玻璃油墨的制备与性能

采取自制的调墨油、耐酸钢化颜料黑(低熔点玻璃粉和高温陶瓷黑色素的混合物)和助剂制备了抗粘、耐酸的汽车钢化玻璃油墨,进行了同步热分析,并采用SEM和XRD研究了烧结温度和时间对油墨釉层表面析晶、表面形貌及其对釉层光泽度和耐酸性的影响,确定了油墨的最佳烧结温度和时间.结果显示:低熔点玻璃粉的软化点为512℃,与调墨油树脂的最终分解温度(470℃)较接近,从而在600～700℃的烧结温度范围内可以充分熔融流动并代替树脂作为连结料;钢化颜料黑在579.4℃开始析晶,起到了降低油墨烧结温度和抗粘的作用;采用SEM和XRD研究了烧结温度和时间对油墨釉层表面析晶、表面形貌及对釉层光泽度和耐酸性的影响,确定了油墨的最佳烧结温度和时间分别为660℃和4 min;所制备的油墨具有良好的抗粘性、耐酸性以及较好的光泽度.     

Hydrothermal synthesis and photoluminescence behavior of CeO<Subscript>2</Subscript> nanowires with the aid of surfactant PVP

Well-crystalline CeO₂ nanowires were prepared via a surfactant-assisted hydrothermal process. Reaction temperature and reaction time were changed for the determination of optimal synthesis parameters. The as-obtained products were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and field emission scanning electron microscopy (FESEM). The results show that single crystal CeO₂ nanowires with high yield and good uniformity can be obtained hydrothermally at 180°C for 12 h with the aid of 2.0 g surfactant (polyvinyl pyrrolidone, PVP). The role of PVP was then discussed and a possible growth mechanism was proposed. Moreover, room temperature photoluminescence (PL) spectra were obtained for these CeO₂ nanowires, which are believed to be related to the abundant defects in these nanostructures.     

基于C/S结构的城市公交监控系统设计

介绍了一种基于C/S结构的城市公交车监控系统,阐述了在Delphi编程环境下如何利用socket编程机制实现客户端与服务器的数据交换,实现了城市公交监控系统的设计。     

Low power and high speed explicit-pulsed double-edge triggered level converting flip-flop

Variable supply voltage-clustered voltage scaling (VS-CVS) scheme can be very effective in reducing power consumption of CMOS circuits without degrading system performance. Level converting flip-flops (LCFFs) are key elements in the CVS scheme. In this paper, a new explicit-pulsed double-edge triggered level converting flip-flop (nEP-DET-LCFF) is proposed, which employs double-edge triggering technique, dynamic structure, explicit pulse generator,conditional discharge technique and proper arrangement of stacked nMOS transistors to efficiently perform latching and level converting functions simultaneously. The proposed nEP-DET-LCFF combines merits of both conventional explicit-LCFFs and implicit-LCFFs. Simulation shows the proposed nEP-DET-LCFF has improvement of 19.2%～46% in delay, and 19.4%～52.9% in power-delay product (PDP) as compared with the published LCFFs.     

促进山西转型发展的研究

随着经济全球化进程的加快,中国经济发展的战略重点已开始由沿海地区向中部地区转移,给山西发展带来了大好机遇。文章从山西的优势、瓶颈问题及解决对策等方面进行了阐述,必将对山西转型发展起到一定的借鉴作用。